kbuild: collect shorthands into scripts/Kbuild.include

The shorthand "clean" is defined in both the top Makefile and
scripts/Makefile.clean.  Likewise, the "hdr-inst" is defined in
both the top Makefile and scripts/Makefile.headersinst.

To reduce code duplication, this commit collects them into
scripts/Kbuild.include like the "build" and "modbuiltin" shorthands.
It requires scripts/Makefile.clean to include scripts/Kbuild.include,
but its impact on the performance of "make clean" should be
negligible.
Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Signed-off-by: Michal Marek <mmarek@suse.cz>

Makefile

@@ -1035,8 +1035,6 @@ firmware_install: FORCE
 #Default location for installed headers
 export INSTALL_HDR_PATH = $(objtree)/usr
 
-hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj
-
 # If we do an all arch process set dst to asm-$(hdr-arch)
 hdr-dst = $(if $(KBUILD_HEADERS), dst=include/asm-$(hdr-arch), dst=include/asm)
 
@@ -1580,11 +1578,6 @@ ifneq ($(cmd_files),)
   include $(cmd_files)
 endif
 
-# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=dir
-# Usage:
-# $(Q)$(MAKE) $(clean)=dir
-clean := -f $(srctree)/scripts/Makefile.clean obj
-
 endif	# skip-makefile
 
 PHONY += FORCE

scripts/Kbuild.include

@@ -179,6 +179,18 @@ build := -f $(srctree)/scripts/Makefile.build obj
 # $(Q)$(MAKE) $(modbuiltin)=dir
 modbuiltin := -f $(srctree)/scripts/Makefile.modbuiltin obj
 
+###
+# Shorthand for $(Q)$(MAKE) -f scripts/Makefile.clean obj=
+# Usage:
+# $(Q)$(MAKE) $(clean)=dir
+clean := -f $(srctree)/scripts/Makefile.clean obj
+
+###
+# Shorthand for $(Q)$(MAKE) -rR -f scripts/Makefile.headersinst obj=
+# Usage:
+# $(Q)$(MAKE) $(hdr-inst)=dir
+hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj
+
 # Prefix -I with $(srctree) if it is not an absolute path.
 # skip if -I has no parameter
 addtree = $(if $(patsubst -I%,%,$(1)), \

scripts/Makefile.clean

@@ -7,10 +7,7 @@ src := $(obj)
 PHONY := __clean
 __clean:
 
-# Shorthand for $(Q)$(MAKE) scripts/Makefile.clean obj=dir
-# Usage:
-# $(Q)$(MAKE) $(clean)=dir
-clean := -f $(srctree)/scripts/Makefile.clean obj
+include scripts/Kbuild.include
 
 # The filename Kbuild has precedence over Makefile
 kbuild-dir := $(if $(filter /%,$(src)),$(src),$(srctree)/$(src))

scripts/Makefile.headersinst

@@ -122,7 +122,6 @@ $(check-file): scripts/headers_check.pl $(output-files) FORCE
 endif
 
 # Recursion
-hdr-inst := -rR -f $(srctree)/scripts/Makefile.headersinst obj
 .PHONY: $(subdirs)
 $(subdirs):
 	$(Q)$(MAKE) $(hdr-inst)=$(obj)/$@ dst=$(_dst)/$@